Patent application title: Central information processing system and method for service robot having layered information structure according to recognition and reasoning level

Abstract:

Provided are a central information processing system and a method for a
service robot. The system includes a broker unit including at least one
of interfaces for analyzing an information request from a corresponding
service robot, transforming a format of the requested information to a
robot-readable format, and transmitting the transformed information to
the service robot, a spatial information manager for hierarchically
composing and storing spatial information according to a
recognition/reasoning level, searching spatial information requested by
the broker unit, and returning the searched spatial information, an
object information manager for hierarchically composing and storing
object information about objects according to a recognition/reasoning
level, searching object information requested by the broker unit, and
returning the searched object information, and a space and object
reasoning unit for searching and reasoning upper layer information about
the object or space using lower layer information obtained from real
environment or object, or searching and reasoning lower layer information
to be used for comprehension of the object or space from upper layer
information.

Claims:

1. A central information processing system for a service robot, which
communicates with at least one of mobile service robots in an indoor,
comprising:a broker unit including at least one of interfaces
corresponding to the service robots where each of the interfaces analyzes
an information request from a corresponding service robot, transforms a
format of the requested information to a format analyzable by the
corresponding service robot, and transmits the transformed information to
the service robot;a spatial information manager for hierarchically
composing and storing spatial information for the indoor according to a
recognition/reasoning level, searching spatial information requested by a
spatial information request of the broker unit, and returning the
searched spatial information;an object information manager for
hierarchically composing and storing object information about objects in
the indoor according to a recognition/reasoning level, searching object
information requested by an object information request of the broker
unit, and returning the searched object information; anda space and
object reasoning unit for searching and reasoning upper layer information
about the object or space using lower layer information obtained from
real environment or object, or searching and reasoning lower layer
information to be used for comprehension of the object or space from
upper layer information.

2. The central information processing system of claim 1, wherein the
spatial information or the object information includes:an actual
measurement information layer including actual measurement information;a
photometric information layer including photometric features;a geometric
information layer including information about sub-parts obtained by
dividing an object or a space by a geometric structure;a structural
information layer including information obtained by dividing constituent
elements of a space or an object and symbolizing and layering information
about the divided constituent elements;a topological information layer
including information for representing locations of objects and obstacles
in a space and accessibility information for gripping an object;a generic
information layer including information about generic models of a space,
an object, and constituent elements of the space and the object;a
spatio-temporal information layer including information about variation
and relation of objects or a space according to a time and a space; anda
reasoning information layer including reasoning information for reasoning
about a space, an object or states of the space or the object from object
or spatial information of lower information layers.

3. The central information processing system of claim 2, wherein the
actual measurement information layer for a space includes base map
information having geometric information of an indoor space,the
photometric information layer for a space includes a photometric feature
map of an indoor space,the geometric information layer for a space
includes geometric information of sub-parts obtained by dividing an
indoor space geometrically,the topological information layer for a space
includes a global coordinate or a pose of an object, or information about
an object recognized as an obstacle,the generic information layer for a
space includes semantic information for the space or constituent elements
of the space, andthe spatio-temporal information layer for a space
includes a brightness of light, a direction of lighting, a temperature,
and a humidity, which vary according to a temporal and spatial state of
an indoor.

4. The central information processing system of claim 3, wherein the
actual measurement information layer for an object includes information
of 2D/3D raw information that stores 2D or 3D representation data
obtained by actually measuring an object,the topological information
layer for an object includes information about accessible directions
represented by a plurality of 3D contact points and 3D directional
vectors,the spatio-temporal information layer for an object includes
information about an object-space temporal dependency, an object presence
and spatiotemporal dependency, an object-object spatiotemporal
dependency, an object-function spatiotemporal dependency, and an
object-physical feature spatiotemporal dependency, andthe reasoning
information layer for an object includes information about an evidence
structure formed as a graph representing relation between information of
lower information layers as a probability.

6. The central information processing system of clam 3, wherein the
obstacle information includes information represented as mesh or cell.

7. The central information processing system of claim 4, wherein the 2D or
3D representation data includes at least one of:a 2D raw image calculated
through at least two of camera angles;depth data obtained from one of a
laser scanner, a stereo camera, a structured light camera; andmesh data
generated from the depth data.

8. The central information processing system of claim 1, wherein the
spatial information manager or the object information manager composes
and stores the spatial information or the object information in ontology,
andthe space and object reasoning unit performs reasoning based on
ontology.

9. The central information processing system of claim 4, wherein the
interface composes a united map by combining information about a base map
of the actual measurement information layer for a space and
object/obstacle location information of the topological information layer
and provides the united map to the service robot, if the corresponding
service robot requests a map.

10. The central information processing system of claim 1, further
comprising a mission analysis manager for composing a probability based
behavior structure based on a given mission, which decides unit behaviors
to perform by a robot, and storing the composed probability based
behavior structure, returning the probability based behavior structure in
response to a request from the broker unit or extracting unit behavior to
perform and necessary information by analyzing the given mission and
returning the extracted unit behavior and the extracted necessary
information.

11. The central information processing system of claim 10, wherein the
mission analysis manager composes the behavior structure in a Bayesian
network having a probabilistic precedence relation of perception data, an
evidence structure behaviors, anddecides an optimal path based on a
probability of the precedence relation and extract behaviors on the
selected path as unit behaviors to perform.

12. A method for processing information for service robots using a central
information processing system communicating with at least one of mobile
service robots in an indoor, comprising the steps of:a) hierarchically
composing and storing spatial information and object information for the
indoor according to a recognition/reasoning level;b) composing interface
for each service robot, analyzing an information request of the service
robot, transforming a format of the requested information to a format
analyzable by the service robot, and transmitting the transformed
information to the robot;c) receiving an information searching request
for searching a spatial information or an object information from the
robot;e) determining whether reasoning is required for searching
information or not, and searching and reasoning upper layer information
about the object or space using lower layer information obtained from
real environment or object, or searching and reasoning lower layer
information to be used for comprehension of the object or space from
upper layer information;f) searching requested object information or
requested spatial information; andg) transmitting searched spatial
information or searched object information to the requesting robot.

13. The method of claim 12, wherein the spatial information or the object
information includes:an actual measurement information layer including
actual measurement information;a photometric information layer including
photometric features;a geometric information layer including information
about sub-parts obtained by dividing an object or a space by a geometric
structure;a structural information layer including information obtained
by dividing constituent elements of a space or an object and symbolizing
and layering information about the divided constituent elements;a
topological information layer including information for representing
locations of objects or obstacles in a space;a generic information layer
including information about generic models of a space, an object, or
constituent elements of the space or the object;a spatio-temporal
information layer including information about variation and relation of
objects or a space according to a time and a space; anda reasoning
information layer including reasoning information for reasoning about a
space, an object or states of the space and the object from object or
spatial information of lower information layers.

14. The method of claim 13, wherein the actual measurement information
layer for a space includes base map information having geometric
information of an indoor space,the photometric information layer for a
space includes a photometric feature map of an indoor space,the geometric
information layer for a space includes geometric information of sub-parts
obtained by dividing an indoor space geometrically,the topological
information layer for a space includes a global coordinate or a pose of
an object, or information about an object recognized as an obstacle,the
generic information layer for a space includes semantic information for
the space or constituent elements of the space, andthe spatio-temporal
information layer for a space includes a brightness of light, a direction
of lighting, a temperature, and a humidity, which vary according to a
temporal and spatial state of an indoor.

15. The method of clam 13, wherein the actual measurement information
layer for an object includes information of 2D/3D raw information that
stores 2D or 3D representation data obtained by actually measuring an
object,the topological information layer for an object includes
information about accessible directions represented by a plurality of 3D
contact points and 3D directional vectors,the spatio-temporal information
layer for an object includes information about an object-space temporal
dependency, an object presence and spatiotemporal dependency, an
object-object spatiotemporal dependency, an object-function
spatiotemporal dependency, and an object-physical feature spatiotemporal
dependency, andthe reasoning information layer for an object includes
information about an evidence structure formed as a graph representing
relation between information of lower information layers as a
probability.

17. The method of clam 13, wherein the obstacle information includes
information represented as mesh or cell.

18. The method of claim 15, wherein the 2D or 3D representation data
includes at least one of:a 2D raw image calculated through at least two
of camera angles;depth data obtained from one of a laser scanner, a
stereo camera and a structured light camera;mesh data generated from the
depth data.

19. The method of claim 12, wherein in the step a), the spatial
information or the object information is composed and stored in ontology,
andin the step e), reasoning is performed based on ontology.

20. The method of claim 13, wherein in the step g), if requested
information includes information about a base map of the actual
measurement information layer for a space and object/obstacle location
information of the topological information layer, a united map is
composed by combining the information about the base map and the
object/obstacle location information.

21. The method of claim 12, further comprising the steps of:a0) composing
a probability based behavior structure based on a given mission, which
decides unit behaviors to perform by a robot, and storing the composed
probability based behavior structure before the step a); andd) returning
the behavior structure in response to a searching request of the robot or
extracting unit behaviors to perform and necessary information to perform
the unit behavior by analyzing the given mission and returning the
extracted unit behaviors and the extracted necessary information after
the step c).

22. The method of claim 21, wherein in the step a0), the behavior
structure is composed in a Bayesian network having a probabilistic
precedence relation of perception data, an evidence structure and
behaviors, andin the step d), an optimal path is decided based on a
probability of the precedence relation and behaviors on the selected path
are extracted as unit behaviors to perform.

23. A computer readable recording medium for storing a method for
processing information for service robots using a central information
processing system communicating with at least one of mobile service
robots in an indoor, the method comprising:a) hierarchically composing
and storing spatial information and object information for the indoor
according to a recognition/reasoning level;b) composing interface for
each service robot, analyzing an information request of the service
robot, transforming a format of the requested information to a format
analyzable by the service robot, and transmitting the transformed
information to the robot;c) receiving an information searching request
for searching a spatial information or an object information from the
robot;e) determining whether reasoning is required for searching
information or not, and searching and reasoning upper layer information
about the object or space using lower layer information obtained from
real environment or object, or searching and reasoning lower layer
information to be used for comprehension of the object or space from
upper layer information;f) searching requested object information or
requested spatial information; andg) transmitting searched spatial
information or searched object information to the requesting robot.

[0002]The present invention relates to central information processing
system and method for hierarchically dividing and integrally managing
information about an indoor space and objects therein based on a
recognition/reasoning level and providing spatial and object information
to mobile service robots according to a recognition/reasoning level of
each robot.

BACKGROUND

[0003]In general, a mobile service robot performs various basic operations
in an indoor environment. For example, the mobile service robot
recognizes an object or a situation, navigates to a predetermined
destination, grips a predetermined object, collects information about a
predetermined object, and stores collected information in a database. The
mobile service robot must have capability of performing operations
requiring high level technologies such as simultaneous localization and
map building (SLAM), self-modeling, and categorization. There have been
many researches in progress for individually developing each of
high-intelligent functions of a mobile service robot.

[0004]However, if a mobile service robot is built by simply combining such
individually developed functions together, compatibility between
functional modules may deteriorate because a mobile service robot may
have different data formats and different memories according to each
function. Also, large amount of duplicated information may be generated
because each of robots has similar information respectively. It is
inefficient in a view of data operability. For example, when a mobile
service robot receives a mission of fetching a green tea in a
refrigerator at a kitchen, the mobile service robot performs sequence of
operations such as navigation, recognition, and manipulation. If green
tea information for recognition is different from green tea information
for manipulation, and if refrigerator information for navigation is
stored separately from refrigerator information for recognition,
information redundancy may occur because information is not integrally
managed. If such waste continues, inefficiency continuously increases in
managing memory spaces and in compatibility between functional modules.
If a robot collects the same information about a refrigerator, a green
tea, and a kitchen through sensing and perception although the other
robot already has the same sensed or perception information of the
refrigerator, the green tea, and the kitchen, the robots may waste
resources due to spatial/temporal redundancy.

[0005]Also, if service robots were individually developed according to
each of functions, each of the service robots has limited capability to
provide low level services. For example, if a mobile service robot does
not have high level reasoning information or context information for a
space or an object although the mobile service robot has superior
navigation capability using a high level reasoning technique such as
SLAM, the mobile service robot may have low capability of learning
knowledge about environments and objects and understanding relations
thereof. Then, the robot cannot perform operation based on understanding
about a space and an object in an indoor space. For example, the robot
cannot perform an operation for fetching a green tea in a refrigerator at
a kitchen, an operation for bring a cup of juice on a table at a kitchen
to a master sat on sofa at a living room. In order to perform such a high
level operation or service, it is necessary to have a knowledge system or
structure for an object and a space in addition to capability for
accurately navigating to a destination and for building a map. That is, a
robot must understand a space or an object.

[0006]Furthermore, it is more necessary to share information about a space
or an object with robots in an indoor space where a plurality of service
robots operate together. That is, information collected by a service
robot must be shared with the other service robots in the same
environment and the context must be reflected to services provided by the
other service robots. Particularly, if a plurality of robots having
different recognition/reasoning levels are in the same environment, it is
necessary to process and transform spatial and object information
according to a recognition/reasoning level of each robot and to share the
processed and transformed information.

[0007]Therefore, there has been a demand for developing a system for
integrally managing information and sharing the information with various
service robots. Related researches have been partially made, recently.

[0008]A geographic information system (GIS) is one of methods for
effectively representing and managing geometric/spatial information. That
is, the GIS is one of technologies for helping a user to make intelligent
decision. The GIS is also a system that maps data having properties to
multiple layers. In general, the GIS describes only information suitable
to a purpose in detail. The general GIS data is not suitable to a service
robot for performing precise operations in home environment because the
GIS data is limited to an outdoor space or a ground. Also, an indoor
environment has been modeled using computer aided design (CAD) many times
and numerous commercial products thereof have been introduced. The indoor
environment modeling has been standardized through Industrial Foundation
Classes (IFC). However, the requirements of a home service robot are not
satisfied by the CAD because the CAD provides only geometric building
structure information.

[0009]In a web service field, many tries have been made for integrally
managing information about individuals who are an object of providing a
service by a home service robot. That is, the behavior patterns of
individuals are observed, ontology is created based on the observation
data, and new information about an individual is created through
reasoning using the ontology. It is expected that such approach helps a
robot to easily understand requirements of human rather than helping a
robot to perform a given mission.

[0010]Information system approach for physical data or raw data has been
used in fields that collect data limited to characteristics of sensors or
fields that collect raw data processed in a low level. Such collected
information is not suitable for a service robot because the reusability
thereof is low or the collected information cannot be linked with
abstract knowledge.

[0011]Among researches about human voice in a view of Human-Robot
Interaction (HRI), an aurora project was made for linking raw data with
high level abstract knowledge. In the aurora project, a central server
stores vocabularies of human voice and is shared for analyzing
preprocessed data and handling errors. However, an original purpose of
distributed sound recognition is to reduce a bottleneck situation caused
by lack of computational resources in a terminal.

[0012]Also, Orca was introduced as a system for sharing software
components, not as a system for sharing data with robots. The object of
the Orca is to effectively and continuously reuse components by
simplifying general interfaces between components and making use of
components easy. The Orca is realized not only through software component
design but also through effective management of component repository.
However, the Orca is middleware approach for binding connection of
components with repositories as one framework.

[0013]Furthermore, a method for representing information about a space and
objects recognized in a soccer game played with four-foot robots and
storing the information was introduced. However, this method has
shortcoming that robots exchange information only through task share
using a token [reference 1].

[0014]Moreover, another study introduced a method for task based
information generation and robot learning. Robots operating in home or
offices must consider various environments and movements to perform a
given mission. However, it is impossible that a robot perfectly builds
knowledge about environments such as home and office in advance.
Therefore, this study introduced new Teaching Framework as Task
Model-Based Interactive Teaching [reference 2].

[0015]In addition, various approaches were introduced for systemizing
data, information, and knowledge and grafting the systemized data,
information, and knowledge to robots or automation equipment. However, it
is required to newly develop an information processing system that can
satisfy requirements of a service robot.

[0018]The present invention has been proposed in order to provide central
information processing system and method for integrally managing
information about an indoor space and objects therein in order to enable
a plurality of service robots to share the indoor information by
providing necessary indoor information to the service robots and
receiving modified information from the service robots.

[0019]The present invention has been also proposed in order to provide
central information processing system and method for hierarchically
dividing and integrally managing information about an indoor space and
objects therein according to a recognition/reasoning level and providing
spatial information and object information to mobile service robots
according to a recognition/reasoning level of each robot.

[0020]The present invention has been also proposed in order to provide
central information processing system and method for searching and
reasoning information about an object or a space using recognition and
reasoning information ranging from lower information layers and upper
information layers and providing searching and reasoning results.

[0021]In an embodiment of the present invention, a central information
processing system for a service robot, which communicates with at least
one of mobile service robots in an indoor, includes a broker unit, a
spatial information manager, an object information manager, and a space
and object reasoning unit. The broker unit includes at least one of
interfaces corresponding to the service robots. Each of the interfaces
analyzes an information request from a corresponding service robot,
transforms a format of the requested information to a format analyzable
by the corresponding service robot, and transmits the transformed
information to the service robot. The spatial information manager
hierarchically composes and stores spatial information for the indoor
according to a recognition/reasoning level, searches spatial information
requested by a spatial information request of the broker unit, and
returns the searched spatial information. The object information manager
hierarchically composes and stores object information about objects in
the indoor according to a recognition/reasoning level, searches object
information requested by an object information request of the broker
unit, and returns the searched object information. The space and object
reasoning unit searches and reasons upper layer information about the
object or space using lower layer information obtained from real
environment or object, or searches and reasons lower layer information to
be used for comprehension of the object or space from upper layer
information.

[0022]In the central information processing system for a service robot
according to the present invention, the spatial information or the object
information may include: an actual measurement information layer
including actual measurement information; a photometric information layer
including photometric features; a geometric information layer including
information about sub-parts obtained by dividing an object or a space by
a geometric structure; a structural information layer including
information obtained by dividing constituent elements of a space or an
object and symbolizing and layering information about the divided
constituent elements; a topological information layer including
information for representing locations of objects and obstacles in a
space and accessibility information for gripping an object; a generic
information layer including information about generic models of a space,
an object, and constituent elements of the space and the object; a
spatio-temporal information layer including information about variation
and relation of objects or a space according to a time and a space; and a
reasoning information layer including reasoning information for reasoning
about a space, an object or states of the space or the object from object
or spatial information of lower information layers.

[0023]In the central information processing system for a service robot
according to the present invention, the actual measurement information
layer for a space may include base map information having geometric
information of an indoor space. The photometric information layer for a
space may include a photometric feature map of an indoor space. The
geometric information layer for a space may include geometric information
of sub-parts obtained by dividing an indoor space geometrically. The
topological information layer for a space may include a global coordinate
or a pose of an object, or information about an object recognized as an
obstacle. The generic information layer for the space may include
semantic information for a space or constituent elements of the space.
The spatio-temporal information layer for a space may include a
brightness of light, a direction of lighting, a temperature, and a
humidity, which vary according to a temporal and spatial state of an
indoor.

[0024]In the central information processing system for a service robot
according to the present invention, the actual measurement information
layer for an object may include information of 2D/3D raw information that
stores 2D or 3D representation data obtained by actually measuring an
object. The topological information layer for an object may include
information about accessible directions represented by a plurality of 3D
contact points and 3D directional vectors. The spatio-temporal
information layer for an object may include information about an
object-space temporal dependency, an object presence and spatiotemporal
dependency, an object-object spatiotemporal dependency relation, an
object-function spatiotemporal dependency, and an object-physical feature
spatiotemporal dependency. The reasoning information layer for an object
may include information about an evidence structure formed as a graph
representing relation between information of lower information layers as
a probability.

[0025]In the central information processing system for a service robot
according to the present invention, the photometric feature may include
information such as Scale Invariant Feature Transform (SIFT), Harris
Corner, color, and line.

[0026]In the central information processing system for a service robot
according to the present invention, the obstacle information may include
information represented as mesh or cell.

[0027]In the central information processing system for a service robot
according to the present invention, the 2D or 3D representation data may
include at least one of: a 2D raw image calculated through at least two
of camera angles; depth data obtained from one of a laser scanner, a
stereo camera, a structured light camera; and mesh data generated from
the depth data.

[0028]In the central information processing system for a service robot
according to the present invention, the spatial information manager or
the object information manager may compose and store the spatial
information or the object information in ontology, and the space and
object reasoning unit may perform reasoning based on ontology.

[0029]In the central information processing system for a service robot
according to the present invention, the interface may compose a united
map by combining information about a base map of the actual measurement
information layer for a space and object/obstacle location information of
the topological information layer and provide the united map to the
service robots, if the corresponding service robot requests a map.

[0030]In the central information processing system for a service robot
according to the present invention, the central information processing
system may further include a mission analysis manager for composing a
probability based behavior structure based on a given mission, which
decides unit behaviors to perform by a robot, and storing the composed
probability based behavior structure, returning the probability based
behavior structure in response to a request from the broker unit or
extracting unit behavior to perform and necessary information by
analyzing the given mission and returning the extracted unit behavior and
the extracted necessary information.

[0031]In the central information processing system for a service robot
according to the present invention, the mission analysis manager may
compose the behavior structure in a Bayesian network having a
probabilistic precedence relation of perception data, an evidence
structure and behaviors, and decide an optimal path based on a
probability of the precedence relation and extract behaviors on the
selected path as unit behaviors to perform.

[0032]Further, in another embodiment of the present invention, a method
for processing information for service robots using a central information
processing system communicating with at least one of mobile service
robots in an indoor, including the steps of: a) hierarchically composing
and storing spatial information and object information for the indoor
according to a recognition/reasoning level; b) composing interface for
each service robot for analyzing an information request of the service
robots, transforming a format of the requested information to a format
analyzable by the service robot, and transmitting the transformed
information to the robots; c) receiving an information searching request
for searching a spatial information or an object information from the
robots; e) determining whether reasoning is required for searching
information or not, and searching and reasoning upper layer information
about the object or space using lower layer information obtained from
real environment or object, or searching and reasoning lower layer
information to be used for comprehension of the object or space from
upper layer information; f) searching requested object information or
requested spatial information; and g) transmitting searched spatial
information or searched object information to the requesting robot.

[0033]In the central information processing method for service robots
according to the present invention, the spatial information or the object
information may include: an actual measurement information layer
including actual measurement information; a photometric information layer
including photometric features; a geometric information layer including
information about sub-parts obtained by dividing an object or a space by
a geometric structure; a structural information layer including
information obtained by dividing constituent elements of a space or an
object and symbolizing and layering information about the divided
constituent elements; a topological information layer including
information for representing locations of objects or obstacles in a
space; a generic information layer including information about generic
models of a space, an object, or constituent elements of the space or the
object; a spatio-temporal information layer including information about
variation and relation of objects or a space according to a time and a
space; and a reasoning information layer including reasoning information
for reasoning about a space, an object or states of the space or the
object from object or spatial information of lower information layers.

[0034]In the central information processing method for service robots
according to the present invention, the actual measurement information
layer for a space may include base map information having geometric
information of an indoor space. The photometric information layer for a
space may include a photometric feature map of an indoor space. The
geometric information layer for a space may include geometric information
of sub-parts obtained by dividing an indoor space geometrically. The
topological information layer for a space may include a global coordinate
or a pose of an object, or information about an object recognized as an
obstacle. The generic information layer for a space may include semantic
information for the space or constituent elements of the space. The
spatio-temporal information layer for a space may include a brightness of
light, a direction of lighting, a temperature, and a humidity, which vary
according to a temporal and spatial state of an indoor.

[0035]In the central information processing method for service robots
according to the present invention, the actual measurement information
layer for an object may include information of 2D/3D raw information that
stores 2D or 3D representation data obtained by actually measuring an
object. The topological information layer for an object may include
information about accessible directions represented by a plurality of 3D
contact points and 3D directional vectors. The spatio-temporal
information layer for an object may include information about an
object-space temporal dependency, an object presence and spatiotemporal
dependency, an object-object spatiotemporal dependency, an
object-function spatiotemporal dependency, and an object-physical feature
spatiotemporal dependency. The reasoning information layer for an object
may include information about an evidence structure formed as a graph
representing relation between information of lower information layers as
a probability.

[0036]In the central information processing method for service robots
according to the present invention, the photometric feature may include
information such as Scale Invariant Feature Transform (SIFT), Harris
Corner, color, and line.

[0037]In the central information processing method for service robots
according to the present invention, the obstacle information may include
information about obstacles represented as mesh or cell.

[0038]In the central information processing method for service robots
according to the present invention, the 2D or 3D representation data may
include at least one of: a 2D raw image calculated through at least two
of camera angles; depth data obtained from one of a laser scanner, a
stereo camera and a structured light camera; and mesh data generated from
the depth data.

[0039]In the central information processing method for service robots
according to the present invention, in the step a), the spatial
information or the object information may be composed and stored in
ontology. In the step e), reasoning may be performed based on ontology.

[0040]In the central information processing method for service robots
according to the present invention, in the step g), if requested
information includes information about a base map of the actual
measurement information layer for a space and object/obstacle location
information of the topological information layer, a united map may be
composed by combining the information about the base map and the
object/obstacle location information.

[0041]In the central information processing method for service robots
according to the present invention, the method may further include the
steps of: a0) composing a probability based behavior structure based on a
given mission, which decides unit behaviors to perform by a robot, and
storing the composed probability based behavior structure before the step
a); and d) returning the behavior structure in response to a searching
request of the robot or extracting unit behaviors to perform and
necessary information to perform the unit behavior by analyzing the given
mission and returning the extracted unit behaviors and the extracted
necessary information after the step c).

[0042]In the central information processing method for service robots
according to the present invention, in the step a0), the behavior
structure may be composed in a Bayesian network having a probabilistic
precedence relation of perception data, an evidence structure and
behaviors. In the step d), an optimal path may be decided based on a
probability of the precedence relation and behaviors on the selected path
are extracted as unit behaviors to perform.

[0043]In still another embodiment, a computer readable recording medium
stores the method for processing information for service robots using a
central information processing system communicating with at least one of
mobile service robots in an indoor according to the another embodiment.

DRAWINGS

[0044]The patent or application file contains at least one drawing
executed in color. Copies of this patent or patent application
publication with color drawing(s) will be provided by the Office upon
request and payment of the necessary fee.

[0045]FIG. 1 is a diagram illustrating an overall system for performing
central information processing system and method of a service robot in
accordance with an embodiment of the present invention.

[0046]FIG. 2 is a block diagram illustrating a central information
processing system for a service robot in accordance with an embodiment of
the present invention.

[0047]FIG. 3 is a diagram illustrating an information structure of a
central information processing system in accordance with an embodiment of
the present invention.

[0048]FIG. 4 is a diagram illustrating information layers of a space and
an object in accordance with an embodiment of the present invention.

[0049]FIG. 5a and FIG. 5b are diagrams illustrating an actual map and a
base map in accordance with an embodiment of the present invention.

[0050]FIG. 6a is a diagram illustrating a photometric feature (SIFT)
extracted from a space in accordance with an embodiment of the present
invention.

[0051]FIG. 6b is a diagram illustrating a photometric feature (SIFT) of a
space information in a 3D map in accordance with an embodiment of the
present invention

[0052]FIG. 7a is a diagram exemplary illustrating obstacles in Octree that
is a cell based representation method in accordance with an embodiment of
the present invention.

[0053]FIG. 7b is a diagram illustrating an indoor space and objects in
accordance with an embodiment of the present invention.

[0054]FIG. 8 is a diagram illustrating an evidence structure in a
reasoning information layer for a space in accordance with an embodiment
of the present invention.

[0055]FIG. 9 shows an ER table of a united map in accordance with an
embodiment of the present invention.

[0056]FIG. 10a is a diagram showing a result of modeling a pencil, which
is a 3D object, in a x3d file of CAD forms in accordance with an
embodiment of the present invention.

[0058]FIG. 11 is a diagram illustrating object configuration information
in a structural information layer in accordance with an embodiment of the
present invention.

[0059]FIG. 12a is a diagram illustrating an accessible direction to an
object in a topological information layer in accordance with an
embodiment of the present invention.

[0060]FIG. 12b shows contact points of an object in a topological
information layer in accordance with an embodiment of the present
invention.

[0061]FIG. 13 is a diagram illustrating a generic model of a cup in
accordance with an embodiment of the present invention.

[0062]FIG. 14 is a diagram illustrating an evidence structure of an object
in accordance with an embodiment of the present invention.

[0063]FIG. 15 is a diagram illustrating a behavior structure represented
by a Bayesian network in accordance with an embodiment of the present
invention.

[0064]FIG. 16 is a diagram illustrating a robot used in simulations
according to an embodiment of the present invention.

[0065]FIG. 17 is a diagram illustrating input/output relation of a map DB
in a spatial information manager in a simulation according to an
embodiment of the present invention.

[0066]FIG. 18 is a time diagram used in a simulation according to an
embodiment of the present invention.

[0067]FIG. 19 is a diagram illustrating a 3D map (left) and a united SLAM
map (right) provided through a manual according to an embodiment of the
present invention.

[0068]FIG. 20 is a diagram illustrating a navigation simulation using a
path planner of a robot according to an embodiment of the present
invention.

[0069]FIG. 21 is a diagram illustrating similar object models stored in a
structural information layer according to an embodiment of the present
invention.

[0070]FIG. 22 is a diagram illustrating generation of initial particles
using ontology in a simulation according to an embodiment of the present
invention.

[0071]FIG. 23 is a diagram illustrating steps of recognizing a space or an
object in a simulation according to an embodiment of the present
invention.

[0072]FIG. 24 is a flowchart illustrating communication between a robot
and a central information processing system while a robot is navigating
in another simulation in accordance with an embodiment of the present
invention.

[0073]FIG. 25 is a flowchart illustrating steps of entering a room and
finding a target object for performing a given mission in another
simulation in accordance with an embodiment of the present invention.

[0074]FIG. 26 is a flowchart illustrating a method for processing
information for a service robot in accordance with an embodiment of the
present invention.

DESCRIPTION

[0075]Hereinafter, embodiments of the present invention will be described
in detail with reference to the accompanying drawings.

[0076]Throughout the specification, like numeral references denote like
elements, and descriptions thereof are omitted.

[0077]FIG. 1 is a diagram illustrating an overall system for performing
central information processing system and method of a service robot in
accordance with an embodiment of the present invention.

[0078]As shown in FIG. 1, the central information processing system 30
according to the present invention includes a database 20. The central
information processing system 30 transmits and receives information
through communicating with a plurality of mobile service robots 10.

[0079]The information processing system 30 exchanges information with the
mobile service robots 10 through wireless communication. The wireless
communication can be made through any wireless communication protocols
such as wireless LAN, radio frequency, and Bluetooth. However, the
wireless communication protocols must be capable of covering an indoor
space. For example, IrDA may not be suitable for the information
processing system 30 because the coverage thereof is small. If a building
is huge or the coverage of an employed wireless communication protocol is
small, repeaters may be disposed at predetermined locations in an indoor
space. Also, it is possible to employ ultra wide band wireless
communication protocols such as Wibro, HSDPA, WiFi, and Wimax. Since the
above described wireless communication protocols are well known to those
skilled in the art, detailed description thereof is omitted.

[0080]The database 20 may be a general relational database. Also, the
database 20 may be ontology storage if object/spatial information is
composed as ontology. That is, the database 20 is a well-known database
having a proper structure according to a format of data of the present
invention. The database 20 may employ a well-known search engine for
managing and searching the database 20. For example, the database 20 may
be an ontology storage including middleware such as an engine for
reasoning ontology.

[0081]The mobile service robot 10 is an intelligent service robot that is
movable in an indoor space and performs given missions. The robot
includes sensors such as an ultra sonic sensor, an infrared sensor, a
laser sensor, a general camera, a laser scanner, a stereo camera,
microphones, etc. The robot 10 includes functions for recognizing an
object or own position or reasoning operation by analyzing measured
values and images from the sensors. Also, the mobile service robot 10
performs recognition, navigation, manipulation, and autonomous
object/environment modeling. Furthermore the mobile service robot 10
includes semantic information about spaces, objects, or relation between
a space and an object and performs semantic reasoning based on the
semantic information. That is, the mobile service robots 10 may have
different recognition/reasoning level.

[0082]The mobile service robot 10 requests necessary information to the
central information processing system 30 through communication and
receives the requested information therefrom. Here, the mobile servicer
robot 10 may simply request data stored in the central information
processing system 30 or may receive data processed in the central
information processing system 30. Furthermore, the robot 10 requests
desired data to the central information processing system 30 and the
central information processing system 30 analyzes the request, searches
and provides suitable data according to the received request. Information
updated by a manager of the central information processing system or by
the robot is provided to the other robots again through the central
information processing system 30.

[0083]FIG. 2 is a block diagram illustrating a central information
processing system for a service robot in accordance with an embodiment of
the present invention.

[0084]As shown in FIG. 2, the central information processing system 30
according to the present embodiment includes a database 20, a broker unit
31, a spatial information manager 33, an object information manager 34,
and a space and object reasoning unit 35. In addition, the central
information processing system 30 according to the present embodiment
further includes a mission analysis manager 36.

[0085]The broker unit 31 includes at least one of interfaces 32
corresponding to each of the service robots 10. Each of the interfaces 32
analyzes an information request of a corresponding robot, transforms a
format of the requested information to a predetermined robot-readable
format, and transmits the transformed information to the robot.

[0086]That is, the broker unit 31 includes interfaces 32 corresponding to
the service robots 10 in a one to one manner. For the same type of
service robots, one interface 32 is connected and processes data in
another embodiment of the present invention. In this case, the interface
32 may be configured to have a multiprocessing function for performing a
plurality of operations simultaneously.

[0087]The interface 32 analyzes an information request from a
corresponding service robot 10 and transforms a format of the received
information request to a predetermined format that can be processed in
the central information processing system 30. On the contrary, the
interface 32 receives a result of the information request from the
central information processing system 30 and transforms a format of the
result to a predetermined format analyzable by the service robot. That
is, the interface 32 transforms information to be compatible with the
service robots 10 and the central information processing system 30
although the service robots 10 have different information system from
that of the central information processing system 30. In near future,
robots will become produced as a common tool in a daily life of human,
and various manufacturers will produce intelligent service robots with
different specifications. A user may purchase various types of service
robots and use them in the same indoor space. Therefore, the interface 32
makes such various types of service robots 10 exchange information with
the central information processing system 30.

[0088]The spatial information manager 33 and the object information
manager 34 hierarchically compose information about an indoor space and
objects therein according to a recognition/reasoning level and stores the
layered information. A structure of information layered according to a
recognition and reasoning level will be described with reference to FIG.
3. FIG. 3 is a diagram illustrating an information structure of a central
information processing system in accordance with an embodiment of the
present invention.

[0089]In the present embodiment, the central information processing system
30 includes information layers 40 shown in FIG. 3. The information layers
40 includes an actual measurement information layer 41, a photometric
information layer 42, a geometric information layer 43, a structural
information layer 44, a topological information layer 45, a generic
information layer 46, a spatio-temporal information layer 47 and a
reasoning information layer 48. The information layers 40 according to
the present embodiment is information layered according to a
recognition/reasoning level of a robot. That is, lower information layers
are information obtained by roughly recognizing or reasoning a space or
an object using sensors. Upper information layers are semantic
information about a space or an object, which can be used to high level
reasoning.

[0090]The actual measurement information layer 41 is an information layer
storing actually measured information. That is, the actual measurement
information layer 41 is information about a size and a shape of a
measured object. The actual measurement information for a space operates
as a base map such as a building plan and includes measurements of 3D
shapes or measured sizes. The actual measurement information for an
object is 2D/3D images of an object or intrinsic/extrinsic camera
parameters. The camera parameters include a location of a camera and a
lens size and are used for error calibration.

[0091]The photometric information layer 42 is an information layer storing
photometric features. The photometric information is a set of
predetermined value or geometry obtained by mathematically analyzing
photometric data such as luminance, hue & saturation, and texture of
2D/3D points in an image. Since a robot recognizes objects appeared by
lighting through cameras basically, the photometric feature is very
important to recognize an object. For example, the photometric feature
includes information such as color, Scale Invariant Feature Transform
(SIFT), Harris Corner, and line.

[0092]The geometric information layer 43 is an information layer for
storing information of sub-parts obtained by dividing a space or an
object by geometric structures. Although the geometric information means
information that geometrically represents a shape of an object, the
geometric information also includes information about sub-parts that are
obtained by structurally dividing an object or a space. For example, if a
cup with a handle is recognized using a camera, the handle can be
structurally separated from the cup although the handle is a part of a
cup image. In case of a refrigerator, an upper door, a lower door, a
freezing compartment, a cool chamber, a drawer, and a handle are
structurally dividable parts. In case of a space, a window, a door, a
ceiling, a column, and a corner are structurally dividable parts.

[0093]The structural information layer 44 is an information layer that
divides a space or an object into constituent elements and symbolically
and hierarchically stores the constituent elements. The structural
information is symbolic and hierarchical information for constituent
elements of an object. One building includes a plurality of floors, and
each floor includes rooms and hallways. Each object includes constituent
elements thereof. On the contrary, a room belongs to a floor. A floor
belongs to a building. That is, the structural information is also
information about spatial relations of objects, which are described in a
view of an object. The structural information must be managed to be
related to the geometric sub-parts in the lower layer thereof. Although
the geometric sub-parts in the lower layer are divided based on exterior
features, constitution of an object is divided by a function in the
structural information layer 44. Since an object is divided based on
geometric segments when the object is divided into constituent elements,
a robot can advantageously identify an object by stages. That is, a robot
can identify a door, one of constituent elements for a space, as a
rectangular plate which is a geometric sub-part. It is possible to
inverse recognition. For example, constituent elements of a specific
apartment is divided by a functional feature linked with information in
lower information layers, such as a living room, a bedroom, a kitchen,
and a bath room, and the divided constituent elements are symbolically
represented. For example, a refrigerator is hierarchically divided into
an upper door, a lower door, a freezing compartment, a cool chamber, a
drawer, and a handle, and the divided sub-parts are symbolically
represented.

[0094]The topological information layer 45 is an information layer for
storing information that represents a location of an object or a location
of an obstacle in a predetermined space. The topological information is
information that represents a global location and a pose of an object and
a location and a volume of an obstacle in a predetermined space. The
topological information is also information representing accessibility
for gripping an object. For example, if a kitchen includes a
refrigerator, an electric range, a dish washer, a cup, a dish, and a
spoon, the topological information of the objects are global locations
and poses of the objects in the kitchen. The obstacle information is
information representing unknown objects, and it is represented as mesh
or cell.

[0095]The generic information layer 46 is an information layer that
defines generic models of a space, an object, or constituent elements of
the space and the object and stores the defined general function. The
generic model is a model that represents semantic definitions of
functions, sub-parts and geometry of a space or an object, and relations
therebetween. For example, the function of a door, a constituent element
of a space, is information about a function of a door, which is "a path
for entering to or exiting from a predetermined space" or "can open and
shut". Also, a cup is that "a tool for drinking water". A handle of a cup
is that "a constituent element used for lifting a cup up" and "a
constituent element for gripping a cup". Like the geometric information
layer 43, the sub-parts are constituent elements of a refrigerator, which
are an upper door, a lower door, a freezing compartment, a cool chamber,
a drawer, and a handle. Also, the sub-parts are constituent elements of a
space, which are a window, a door, a ceiling, a column, and a corner. The
sub-parts in the generic information layer 46 are different from the
geometric information layer 43 as follows. The sub-parts in the geometric
information layer 43 are information obtained by dividing instances based
on actually measured data. On the contrary, the sub-parts in the generic
information layer 46 define commonly dividable features of an object or a
space. The geometry means a point, a line, a plane, an oval, a sphere, a
box, etc., and geometric features that a space or an object is generally
supposed to have are defined in the geometry. In a space, an apartment is
divided into general constituent elements such as a living room, a bed
room, a kitchen, and a bath room and semantically classified in the
generic information layer. Lower information layers of the generic
information layer 46 are information about an exterior structure or a
configuration of a specific object. On the contrary, upper information
layers including the generic information layer 46 are information about
semantic information. That is, while classification of configuration in
the lower layers is exterior classification according to a function, the
generic information layer 46 is about semantic information about
configuration.

[0096]The spatio-temporal information layer 47 is an information layer for
storing information about object variation and space variation according
to temporal and spatial change and relations thereof. The spatio-temporal
information is semantic information for relation between entities. In
other view points, the spatio-temporal information is semantic
information about entity variation according to change of corresponding
entity. The entity may be a time, an environment, the other entity, etc.
That is, the spatio-temporal information denotes temporal relation (or
entity variation in a time domain), environmental relation (or entity
variation according to environmental variation), and relation with other
entity (or entity variation according to variation of the other entity).
The spatio-temporal information is information about characteristics of
an indoor space or an object change according to temporal and spatial
states. For example, the spatio-temporal information includes luminance,
a direction of lighting, a temperature, a humidity, etc. Also, the
spatio-temporal information is information about change of an object
location in a time domain and information about influence of a specific
object on the other objects, when the object exists in a specific time
and space.

[0097]The reasoning information layer 48 is an information layer for
storing reasoning information for reasoning a space, objects, or states
of the space or the objects from actually measured states. The reasoning
information is information about a reasoning structure that is composed
using information in lower information layers. For example, the reasoning
information may be an evidence structure composed as a graph based on a
probability for recognizing an object. It is possible to perform
reasoning at lower information layers of the reasoning information layer
48. For example, since the generic information layer and the
spatio-temporal information layer are semantic information, it is
possible to perform semantic reasoning. Further, it is also possible to
perform reasoning for information about exterior structures in lower
information layers of the generic information layer and the
spatio-temporal information layer using methods for searching objects
matched with specific properties or specific features. Since the
reasoning information layer 48 is information for reasoning more
technically based on a probability, the reasoning made in the reasoning
information layer 48 is different from that made in the lower information
layers thereof.

[0098]In overall, the upper information layers are composed based on the
lower information layers. Although each of the information layers may be
embodied individually, entire or a part of the information layers may be
embodied as one data structure. For example, information about all of
layers may be composed in ontology. For example, a class or an instance
of a "cup" is created, all properties are defined from the actual
measurement information layer to the topological information layer, and
information in the generic information layer may be defined as properties
of the class.

[0099]Hereinafter, the information layers will be described in detail with
the spatial information manager 33 and the object information manager 34.

[0100]The spatial information manager 33 hierarchically composes spatial
information about a predetermined indoor space according to a
recognition/reasoning level and stores the composed spatial information.
The spatial information manager 33 also searches spatial information
requested by the broker unit and returns the searched result to the
broker unit. As shown in FIG. 4, the spatial information is composed of
information about eight information layers as described above.

[0101]The actual measurement information layer for a space is a layer for
storing geometric information of an indoor space like the geographic
information system (GIS). That is, the actual measurement information
layer is the most basic information such as a base map like a building
plan. The base map includes a 2D grid map schematically showing
structural information of a predetermined indoor environment and a 3D map
composed in a CAD format according to industrial foundation class (IFC)
2xx specification, which is a basic building plan composing rule and an
international standard format for exchange of document for building
design. Here, the CAD format includes ifcXML and dxf. FIG. 5a is an
actual map, and FIG. 5b is a base map composed based on the actual map of
FIG. 5a. As shown in FIGS. 5a and 5b, the base map include basic
environmental information. The reference coordinate of the base map uses
an X-Y orthogonal coordinate for a horizontal plane and a Z-axis for
vertical component.

[0102]The photometric information layer for a space stores a photometric
feature map for an indoor space. The photometric feature map represents
an image processing result that can be obtained using only luminance
values and color values from an entire image area, such as SIFT, Harris
Corner, and Color. FIG. 6a is a diagram illustrating SIFT extracted from
an indoor environment in accordance with an embodiment of the present
invention, and FIG. 6b is a diagram illustrating SIFT extracted from an
indoor environment in a 3D united map in accordance with an embodiment of
the present invention.

[0103]The geometric information layer for a space stores a geometric
environment structure. That is, an indoor environment is divided into
sub-parts, and information about the sub-parts is stored in the geometric
information layer. For example, environmental objects such as a door, a
window, a wall, and a column, and a global geometric feature such as a
corner, a side, and a plane belong to information stored in the geometric
information layer for a space. Also, the structural relations of them are
also stored in the geometric information layer. A robot 10 uses the
information to recognize its location or to manipulate an environmental
object such as opening and closing a door.

[0104]The structural information layer for a space classifies constituent
elements of a space and symbolically and hierarchically stores
information of the classified constituent elements. Since a building
includes a plurality of floors and a floor includes pathways and rooms,
the structural information symbolically represents each of the
constituent elements. And, the structural information is stored to be
linked with the lower information layers that store the
geometric/photometric feature/actual measurement information. For
example, the structural information of a specific apartment is
information symbolically representing constituent elements of
geometric/photometric feature/actual measurements which are divided by a
functional feature such as a living room, a bed room, a kitchen, and a
bath room.

[0105]The topological information layer for a space is an information
layer for storing information about locations of an object and an
obstacle. The topological information layer represents locations and
poses of movable objects which are used for manipulating on a map. In the
topological information layer, global coordinates and poses of objects
are represented without an object model stored. In the topological
information layer, an unknown object is considered as an obstacle. If a
predetermined object does not have any information in object DB, the
predetermined object is considered as an unknown object. The obstacle is
represented and stored as mesh or cell (eg. Octree). FIG. 7a is a diagram
exemplary illustrating obstacles in Octree that is a cell based
representation method in accordance with an embodiment of the present
invention. FIG. 7b is a diagram illustrating an indoor space and objects
in accordance with an embodiment of the present invention. In an object
modeling reference frame, an origin denotes the center of a target object
for providing a service, an X-axis denotes horizontal components, a
Y-axis denotes vertical components, and a Z-axis denotes depth component.
Coordinates of objects, which are stored and managed in the spatial
information manager 33, moves the object modeling reference frame to the
lowest point in a height direction. That is, the spatial information
manager 33 provides instinctive arrangements and coordinates movements
for the object. Orientation information of objects stored and managed in
the spatial information manager 33 is represented as unit vectors for
world coordinates X, Y, and Z based on each of reference axis of an
object, U, V, and W, or a rotation angle.

[0106]The interface 32 creates a united map by combining information about
a base map and locations of objects and obstacles if a corresponding
robot requests a map. FIG. 9 shows an ER table of a united map in
accordance with an embodiment of the present invention.

[0107]The generic information layer for a space stores generic spatial
models. The generic spatial models represent semantic spaces such as a
living room, a bed room, a family room, and a bath room. The generic
information layer also represents semantic information of constituent
elements of a space such as a door, a window, etc. The generic
information is used to detect a location of a robot 10 and divide areas
semantically.

[0108]The spatio-temporal information layer for a space stores
environmental information. The environmental information means properties
varying according to temporal or spatial states, such as luminance of
light, a direction of lighting including natural lighting, a temperature,
and a humidity. The environmental information is a factor influencing a
robot 10 to perform recognition or modeling services.

[0109]The reasoning information layer for a space stores information for
an evidence structure of the reasoning information layer 48 as described
above. FIG. 8 is a diagram illustrating an evidence structure in a
reasoning information layer for a space in accordance with an embodiment
of the present invention. As shown in FIG. 8, general functions of a
kitchen are cooking, conversation, and a wine bar. The kitchen generally
includes a gas range, a sink, a refrigerator, and a table. A probability
that a predetermined space is a kitchen become close to 1 if all of
related conditions are satisfied. If predetermined number of related
conditions is satisfied, it is possible to assume the predetermined space
as a kitchen. Such information is stored as the evidence structure for a
space.

[0110]The object information manager 34 hierarchically composes object
information of objects in the indoor space according to a
recognition/reasoning level and stores the hierarchical object
information. The object information manager 34 receives a request for
object information from the broker unit, searches the requested object
information, and returns the searched object information to the broker
unit. As shown in FIG. 4, the object information is composed in total of
eight information layers and stored.

[0111]The actual measurement information layer for an object is
information about a raw image. The actual measurement information layer
stores actually-measured 2D/3D raw data of an object, which is obtained
through 2D/3D camera. That is, the actual measurement information is 2D
data calculated through various camera angles and includes raw images and
depth data from a laser scanner, a stereo camera, or a structured light
camera.

[0112]The photometric information layer for an object is information about
photometric features of an object. The photometric information layer
includes information such as color, scale invariant feature transform
(SIFT), Harris corner, line, etc., which are obtained from the raw image.
The photometric information is used as an evidence for object
recognition.

[0113]The geometric information layer for an object is information about
geometric features and stores geometric information of an object in
structural form. The geometric information is obtained from a raw image.
The geometric information layer includes a method for modeling an object
having sub-parts and a method for representing object feature for
understanding information of upper layers and linking with the
information of the upper layers, not a method for generating a model for
object recognition based on rigid body. For example, if an object is a
refrigerator, the object is divided into an upper door, a lower door, a
freezing compartment, a cool chamber, a drawer, and a handle. In case of
a predetermined space, the space is divided into a door, a ceiling, a
column, a corner, etc. FIG. 11 shows a refrigerator as example.

[0114]Well known CAD formats, x3d, dfx, 3ds, wrl, or obj may be used as a
data structure for the geometric information layer for an object, or a
predetermined storage structure may be created. However, it is required
to develop a separate format because all geometric information cannot be
represented in a CAD format. For convenience, a data format of a CAD
model is used in simulations according to the present invention. FIG. 10a
is a diagram showing a modeling result of a pencil, which is a 3D object,
in x3d file that is one of CAD formats in accordance with an embodiment
of the present invention. FIG. 10b is a diagram illustrating a modeling
code of x3d of FIG. 10a .

[0115]The structural information layer for an object is information about
a structure of an object. That is, the information describes constituent
elements of an object. The structural information layer is managed linked
with information in lower information layers which have geometric and
photometric features. For example, a cup includes constituent elements, a
main body and a handle. The constituent element means sub-parts of a cup.
Therefore, it is necessary to be linked with sub-parts information of
lower information layers having the geometric and photometric feature
information. FIG. 11 is a diagram illustrating constituent information of
an object in the structural information layer in accordance with an
embodiment of the present invention. As shown in FIG. 11, a refrigerator
includes a main body, an upper door, a lower door, a freezing
compartment, a cool chamber, and a shelf. In FIG. 11, a left upper
diagram illustrates a main body of a refrigerator, a left lower diagram
illustrates a door of a refrigerator, and a right diagram illustrates a
diagram with the main body and the door combined.

[0116]The topological information layer for an object includes information
that represents accessibility for gripping an object. The accessibility
is one of properties of an object. That is, the topological information
is information related to which part of an object can be gripped by
accessing the object in which direction. FIG. 12a is a diagram
illustrating a direction of accessing an object in the topological
information layer in accordance with an embodiment of the present
invention, and FIG. 12b shows contact points of an object in the
topological information layer in accordance with an embodiment of the
present invention. As shown in FIG. 12, the information includes a
plurality of 3D contact points for gripping the object and accessible
directions represented as 3D direction vectors.

[0117]The generic information layer for an object is an information layer
storing a generic object model. The generic information represents an
object in one abstract structure by gathering common geometric features
of an object together for a specific model or instance in a specific
object class. For example, general features of a cup maybe structurized
into a function of preserving a drinking water, a function of driving a
water, a function of gripping and lifting up, a hollow providing a
predetermined volume for putting a drinking water therein, a handle for
enabling a robot to grip, a cylindrical shape body, an ellipse
representing an upper part of a cup, a concave surface and a convex
surface representing interior and exterior features of a cup. If specific
model of an object, that is, unique instance model of an object are not
provided, the generic information is used to create a model of an object
or to recognize an object. Also, the generic information is used when an
optimal segmentation method for recognizing an object is introduced, when
a function of each sub-part is reasoned by recognizing a sub-part, and
when an effective recognition process is searched according to an object.
FIG. 13 is a diagram illustrating a generic model of a cup in accordance
with an embodiment of the present invention. As shown in FIG. 13, the
generic model of a cup represents functions of a cup in a first level 1,
represents sub-parts of a cup in a second level 2, and represents the
most similar geometry enabling reasoning of each sub-part.

[0118]The spatio-temporal information layer for an object is about context
spatio-temporal information. The context includes an object-space
temporal dependency that represents how a location of an object changes
in a time domain, an object-object spatiotemporal dependency that
represents how an object is influenced by existence of the other object,
an object presence and spatiotemporal dependency that represents effect
influenced to existence of the other objects when a specific object is in
a specific temporal space, an object-function spatiotemporal dependency
that represents how a function of an object changes according to a time
and a space, and an object-physical feature spatiotemporal dependency
that represents what features of an object, such as a shape, a color,
texture, and transparency, are changed according to a time and a space or
according to environmental information.

[0119]The reasoning information layer for an object represents relation
with lower information layers, common senses for object recognition, and
probability of each evidence in a graph as an evidence structure. FIG. 14
is a diagram illustrating an evidence structure.

[0120]The space and object reasoning unit 35 searches and reasons upper
layer information such as semantic information, spatio-temporal
information, common-sense information, evidential information, context
information, or the like, from the given lower layer information.
Meanwhile, the space and object reasoning unit 35 also searches and
reasons lower layer information to be used for comprehension of the
object or space from the upper layer information. The space and object
reasoning unit 35 performs reasoning using reasoning information of the
reasoning information layer, performs semantic reasoning using semantic
information in the generic information layer or the spatio-temporal
information layer, or performs reasoning using a method for searching
objects matched with predetermined properties or features using
information in lower information layers. For example, if there exists a
reasoning structure of the upper information layer that a refrigerator is
usually in the kitchen and the refrigerator is an object that has lines
and a hexahedron as basic geometry primitive, in order to perform a
mission of "find the refrigerator", a process for reasoning the current
location of the refrigerator and, if a plurality of lines is detected, a
process for discriminating what the detected lines are should be
performed simultaneously. This means that a bottom-up process and a
top-down process are conducted at the same time. In case that the mission
is to find a refrigerator and ID of the refrigerator is given, in order
to find the refrigerator, it is required a reasoning process that the
kitchen should be found first (spatio-temporal information layer) and
then it should be reasoned what kind of features and components the
refrigerator has (reasoning information layer/generic information layer).
Using the results of these reasoning processes, the actual
object/environment is recognized and comprehended from the lower layer
object/environment instances (structural information layer/geometric
information layer). This may be considered as a top-down process. At the
same time, if a plurality of lines is detected in a scene, a
discrimination process for identifying whether the lines are for an
air-conditioner or a refrigerator should be performed (structural
information layer/geometric information layer). That is, it needs a
process for reasoning the object identification (generic information
layer/reasoning information layer) using lower layer information. This
may be considered as a bottom-up process. Particularly, the space and
object reasoning unit 35 performs reasoning using an ontology reasoning
engine if the information about a space or object is composed in
ontology.

[0121]The mission analysis manager 36 creates and stores a probability
based behavior structure that decides a unit behavior of a robot from a
given mission and returns a created behavior structure to a robot by a
request from the broker unit. The mission analysis manager 36 also
analyzes a mission given to a robot, extracts a unit behavior to perform
and necessary information for the behavior, and returns the extracted
unit behavior and information to the robot.

[0122]The mission analysis manager 36 creates the behavior structure as a
Bayesian network having a probabilistic precedence relation of perception
data, an evidence structure and behavior, decides an optimal path based
on a probability of the precedence relation, and extracts a behavior on
the path as a unit behavior to perform.

[0123]FIG. 15 is a diagram illustrating a behavior structure in accordance
with an embodiment of the present invention. As shown in FIG. 15, a robot
may receive missions such as "fetch a cup", "find a cup in a room", or
"find and fetch a cup". The mission "fetch a cup" can be divided into
behaviors "find a location of a cup", "navigate to the cup", "grip the
cup", and "return to original location". Also, the mission "find a cup"
can be divided into behaviors "obtain shape and photometric features of a
cup", "look around", "find object having a matched shape in image", "turn
on light if it is dark", "find switch for light", "navigate to switch",
"obtain information for turning on switch " and "turn on the switch as
the information". In this case, the robot analyzes a mission by unit
orders. The robot may refer rules to analyze the missions. However, a
probability based Bayesian network is created with various situations in
the present embodiment because a mission may be divided into various
specific missions such as turning on a light or drawing a curtain back if
it is dark.

[0124]As described above, a Bayesian network of a predetermined mission is
composed in stages, and an optimal path is selected based on a
probability. The robot performs unit behaviors on the selected optimal
path. If the robot fails to perform one of the unit behaviors on the
selected optimal path, the robot performs unit behaviors of a next
optimal path.

[0125]If the robot needs information for performing the unit behaviors,
necessary information thereof is extracted and returned. Here, the
necessary information, for example, includes information about "cup",
"switch", "method for gripping a cup", "method for turning on a switch",
"photometric feature of a cup".

[0126]The interface 32 of the central information processing system
according to the present embodiment processes an information request from
a mobile service robot 10. Hereinafter, the operation of processing the
information request in the interface 32 will be described in detail.

[0127]The interface 32 performs necessary operations for simple
information requests from the mobile service robot 10. That is, if the
mobile service robot 10 request spatial information of location
information of an object and an obstacle, the interface 32 fetches stored
information and transmits the fetched information to the mobile service
robot 10.

[0128]The interface 32 creates a united map by combining spatial
information of a base map information layer and information of an object
and an obstacle location information layer and provides the created
united map to the robot if the robot requests a map. The robot mainly
uses the united map to navigate.

[0129]The interface 32 can also transmit reasoning results. For example,
if the mobile service robot 10 requests spatial information to perform a
mission "fetch a cup", the interface 32 requests the space and object
reasoning unit 35 to reason about details of a cup. Therefore, the
interface 32 detects a location of the reasoned cup at the space and
object reasoning unit 35 and transmits the spatial information from a
current location of the robot 10 to a location of a cup. Here, the
interface 32 may transmit results of recognizing other objects in the
related space as obstacles instead of transmitting information about all
of objects from the current location to the location of the cup. It is
because, the other objects in the related space do not have any meaning
when the robot performs a mission "fetch a cup". That is, the interface
32 may provide only the information according to a recognition/reasoning
level of the service robot 10. For example, when an intelligent mobile
service robot built for cleaning receives a mission "clean a floor", the
interface 32 recognizes all objects on the floor as obstacles and
transmits a united map or an obstacle map composed with the recognized
objects to the intelligent mobile service robot. It is decided according
to a recognition/reasoning level of a service robot 10, and a proper
interface is embodied according to the level thereof. The interface 32
receives information recognized by the service robot 10 and updates
stored information based on the received information. That is, the
central information processing system 30 also enables robots to share
information through updating as well as providing information in one
direction. That is, the central information processing system 30 may
operate as a memory, not a database. For example, if a user has a
medicine, which was on a tea table in the morning, at a lunch time, the
medicine is not on the tea table any more. Such information must be
shared with robots. That is, if an object is disappeared, moved, or newly
located in a predetermined indoor space, a service robot 10 recognizes
states different from spatial information received from the central
information processing system 30 and transmits the recognized information
to the central information processing system 30.

[0130]It is preferable to limit information updated by a robot to
information stored in the lower information layers of the topological
information layer. It is because that the information of the lower
information layers of the topological information layer is exterior
features of an object which are measured through sensing operations of
the robots. However, information stored in the upper information layers
of the topological information layer is semantic information. In order to
sustain reliability of the information, such information must be updated
only by robots having high level intelligence for learning and reasoning.
That is, it is unreliable to change information about an object and
semantic information of upper information layers based on a robot's
determination due to capability and limitation of a service robot up to
now. If a service robot has a reliable spatial recognition ability and
object modeling capability in a near future, the service robot will be
able to update information of the upper information layers.

[0131]As described above, each of the robots accesses the central
information processing system 30, and obtains and modifies information.
Since the central information processing system 30 does not make decision
to reason new data or to control the robots 10, user's capability may be
more important to increase performance of each robot 10 in order to
improve overall performance. However, effective information management
through framework and a layered information policy make input/output more
clear and modules worked together.

[0132]Hereinafter, simulations made using the framework of the central
information processing system 30 according to an embodiment of the
present will be described with reference to FIGS. 16 to 25.

[0133]FIG. 16 is a diagram illustrating a robot used in simulations
according to an embodiment of the present invention. FIG. 17 is a diagram
illustrating input/output relation of a map DB in a spatial information
manager in a simulation according to an embodiment of the present
invention. FIG. 18 is a time diagram used in a simulation according to an
embodiment of the present invention. FIG. 19 is a diagram illustrating a
3D map (left) and a united SLAM map (right) provided through a manual
according to an embodiment of the present invention. FIG. 20 is a diagram
illustrating a navigation simulation using a path planner of a robot
according to an embodiment of the present invention. FIG. 21 is a diagram
illustrating similar object models stored in the geometric information
layer according to an embodiment of the present invention. FIG. 22 is a
diagram illustrating generation of initial particles using ontology in a
simulation according to an embodiment of the present invention. FIG. 23
is a diagram illustrating steps of recognizing a space or an object in a
simulation according to an embodiment of the present invention.

[0134]First Simulation> Vision Based Navigation and SLAM Map Update

[0135]The first simulation was focused to reduce data redundancy and to
guarantee data concurrency and validation among requirements of a central
information processing system for service robots 10. The robots 10 shown
in FIG. 16 include two map update modules. Also, the central information
processing system 30 processes information from SLAM and a manual based
on a policy system that prevents collision and builds a database thereof.
The information from the manual is information input by a system manager.
The information from SLAM is information created by combining information
sensed and recognized by robots 10 in a predetermined indoor space. The
path planner is used to connect the central information processing system
30 and to receive new information from the central information processing
system 30. That is, the central information processing system 30 receives
spatial information from the robots by SLAM, manages overall map based on
the manual, and transmits the map to robots if the robots request a map.

[0136]The result of the simulation is shown in FIGS. 19 and 20. The left
map of FIG. 19 is a 3D map provided beforehand to robots 10 through a
manual, and FIG. 20 is a diagram for describing simulations that
represents data received through vision in Octree, forms an occupancy
grid through SLAM process, and enables a robot 10 to navigate through
paths generated by a path planner using the occupancy grid.

[0137]Second Simulation> 3D Object Recognition

[0138]The second simulation was performed for verifying that information
layers according to the present invention can improve efficiency. In the
second simulation, a robot receives a mission "approach to a refrigerator
for gripping a target object in the refrigerator, find the target object,
juice, in the refrigerator, and detect accurate location of the target
object.

[0139]Since a rough location of the refrigerator is shown in a map stored
in the central information processing system 30, a robot finds,
navigates, and approaches to a refrigerator like the first simulation. If
the robot meets an object similar to the refrigerator shown in FIG. 21
while finding the refrigerator, the robot detects a comparative spatial
location between the robot 10 and the refrigerator using not only
information in the geometric information layer and photometric
information layer but also constraint knowledge for matching, which is
composed as an evidence structure of the reasoning information layer. For
example, locations and the number of horizontal lines are important
information for a robot to discriminate the refrigerator from an air
conditioner. In order to discriminate the refrigerator from a book shelf,
the robot must check a ratio of horizontal lines and vertical lines. If
the robot has difficulty to discriminate the refrigerator from the
similar objects using relations between lines, the robot must use a
reasoning result to match. That is, the robot uses an ontological
inference that a refrigerator needs a handle and an air conditioner does
not need a handle. That is, the robot finds SIFT of a handle from the
photometric information layer the an object based on the reasoning about
the handle and determines whether the object is the refrigerator or not
through handle SIFT matching. FIG. 22 shows line models made based on
ontology reasoning information and geometric features of the object.

[0140]After the robot 10 arrives at the refrigerator, the robot 10 looks
in the refrigerator and starts finding the target object. The robot 10
makes a plan for sensing the target object based on knowledge that a
location of the target object can be further accurately predicted through
SIFT matching when a searching area is sufficiently small and information
in the spatio-temporal information layer that the target object is in the
refrigerator. Such a sensing plan makes the robot 10 to accurately detect
the location of the object. FIG. 23 shows that the robot 10 finds the
target object, juice, using information in the photometric information
layer and the actual measurement information layer after arriving at the
refrigerator.

[0141]It is possible to reduce operation time of a robot by decreasing an
unnecessary searching area for performing a given mission and improving
certainty for found target while searching using layered information
through the central information processing system 30 according to the
present embodiment. It means that the performance of a service robot can
be improved by supporting integral information processing according to
the present invention.

[0142]Third Simulation> Fetch a Cup from a Nth Floor in a Building
A.

[0143]The third simulation according to an embodiment of the present
invention will be described with reference to FIGS. 24 and 25. FIGS. 24
and 25 show a robot performing a mission "fetch a cup from a Nth floor in
a building A" using the central information processing system according
to an embodiment of the present invention.

[0144]At first, the central information processing system 30 must have a
map for the building A and the indoor spaces thereof and object models,
which are input by a system manager in advance, in order to enable a
robot to perform the given mission. The manager performs modeling for a
space and an object on information of each of information layers, as
defined in FIG. 4. Here, the indoor map which is actual measurement
information is stored in a 2D grid map and a CAD model formation
according to IFC 2xx specification, which is a basic building plan
composing rule and an international standard format for building design.
That is, the map is stored in a format of ifcXML or dfx, and the object
is stored in a form of x3d, dfx, 3ds, wrl, and obj. Such information is
registered and stored in the database 20. If it is necessary to modify an
object/map model, related information from the DB is corrected. Then, the
information is updated in a DB server. In order to correct and modify,
the central information processing system 30 must include a modeling unit
(not shown). Since the modeling unit is a well-known commercial graphic
modeling unit such as 3D Architect, Auto CAD, 3D Studio Max, and Maya,
the detail description thereof is omitted. If the robot finds a new
object which was not known and stores the found object in a DB, it may be
required for a manager to directly record information thereof in the DB
because the robot has not information about a name and a category
thereof.

[0145]FIG. 24 is a diagram illustrating communication between a robot and
a central information processing system when the robot navigates to a
room C on a Nth floor in a building A in order to perform a mission
"go Nth floor of a building A and fetch a cup therefrom".

[0146]As a first step, it is necessary to inform the robot of a term of
cup as a specific model required for recognition in order to enable the
robot to understand the cup because the robot 10 does not know what a cup
is. Therefore, the robot requests a location of a target object, the cup,
to the broker unit 31 (or corresponding interface 32). The broker unit 31
reasons about a class of the term "cup" through the spatial object
reasoning unit 35 and confirms that the cup is an object for putting a
drinkable liquid therein and has an separate category among categories of
all objects through reasoning. Then, the broker unit 31 searches the
topological information layer to determine where object corresponding to
the category of cup is generally located, and detects that the object is
generally located on a kitchen or a desk in a room C on the Nth
floor. The broker 31 requests a map for the room C on the Nth floor
to the spatial information manager 33 using the detected information,
confirms if a location of the cup is recorded by analyzing locations of
objects and obstacles in the structural information layer stored in the
spatial information DB 22 and transfers the information thereof to the
robot. The robot 10 locally stores the searched cup location, requests a
map of a current floor where the robot is currently located and a united
map of the Nth floor to the broker unit 31, and downloads and stores
the requested maps in a local map DB in order to navigate to the room C
on the Nth floor. Here, if the robot already stores a united map for
the current floor in the local map DB, the robot does not download the
united map from the broker unit 31.

[0147]Then, the robot finds an elevator to move to the room C on the
Nth floor. The robot checks a rough location of an elevator using
the map for the current floor. While moving, the robot requests an
elevator model to the object information manager 34 through the broker
unit 31 to recognize the elevator and downloads the elevator model from
the object information manager 34. The elevator model is formed of an
evidence structure that represents determination references for object
recognition in the reasoning information layer as a probability graph, a
generic model of the generic information layer representing general
features of an object, and a CAD model representing geometric features of
the geometric information layer. Remaining information layers are filled
with Null values because the elevator model does not have texture and
reflects light excessively. After the robot recognizes the elevator, the
robot is required to push a button, ride the elevator, and operate
buttons on a control panel of the elevator. Therefore, an elevator
interior model is also required. Since the elevator interior model is
spatial information unlike the outside of the elevator, the robot
requests the elevator interior model to the spatial information manager
33 and receives the elevator interior model with a united map from the
spatial information manager 33.

[0148]FIG. 25 is a diagram illustrating steps for entering the room C on
the Nth floor of the building A and finding the target object therefrom
using information provided from the central information processing system
30 according to an embodiment of the present invention in order to
perform the mission "go Nth floor of a building A and fetches a cup
therefrom". If the robot finds unknown objects, steps for including the
unknown objects in the object information are included. If there is no
information about the found unknown object and no generic models for the
found unknown object, operations for determining the found unknown
objects as obstacles and updating spatial information are included.

[0149]When the robot arrives at the Nth floor, the robot navigates to
the room C using the downloaded united map. When the robot arrives at the
room C, the robot needs spatial information (or map information) of the
inside of the room C and information about stationary objects such as a
refrigerator, a washing machine, and a desk and movable objects such as a
cup, a watch, and a chair. Therefore, the robot 10 requests the spatial
information and the object information to the broker unit 31. Then, the
broker unit 31 requests the requested information to the spatial
information manager and the object information manager, receives the
requested information, and transmits the requested information to the
robot 10. The robot 10 receives the requested information and stores in a
local united map DB. Here, since the robot has a limited local storage
capacity, the robot downloads and stores information in an order from
stationary objects to movable objects until a predetermined storage
capacity reaches.

[0150]After the robot enters the room C, if the robot finds an unknown
object, the robot detects overall features thereof and confirms whether
the object of the category having the detected feature is recorded in the
central information processing system 30. The robot 10 requests generic
model information to the broker unit 30. Then, the broker unit 31
receives a result of searching the requested generic model information
from the object information manager and transmits the result to the robot
10. The robot reasons a category of the found object by comparing the
recognized feature with the obtained generic model information. If the
found object belongs to a predetermined class, the robot requests model
data of the category to the broker unit 31. Then, the robot tries to
recognize the unknown object using the received model from the broker
unit 31. If the robot succeeds in recognition of the unknown object, the
robot requests the broker unit 31 to update a location and a pose of the
corresponding object, and the broker unit 31 requests the spatial
information manager 33 to update object/obstacle information of the
topological information layer and register a location and a pose of the
object on the united map.

[0151]If the found object does not belong to any categories or if there is
no specific model data for the found object although the found object
belongs to a predetermined class, the third and fourth steps of FIG. 25
are performed. That is, an unknown object must be considered as an
obstacle, and the information thereof must be reflected. The robot can
navigate and manipulate safely by avoiding the obstacles using the
obstacle information. Finally, the robot must create a model of the
unknown object until a manager inputs information thereof. Therefore, the
robot creates a model of an unknown object and stores the created model
by modeling a shape and features of the unknown object through a modeling
unit. Then, the robot requests the broker unit 31 to update related
information of each information layer, mainly the lower information layer
of the topological information layer, through the spatial information
manager 33.

[0152]Hereinafter, a method for processing information for a service robot
in accordance with an embodiment of the present invention will be
described with reference to FIG. 26. FIG. 26 is a flowchart illustrating
a central information processing method for a service robot in accordance
with an embodiment of the present invention.

[0153]As shown in FIG. 26, the method for processing information for
service robots using a central information processing system
communicating with at least one of service robots in an indoor, includes
the steps of: a) hierarchically composing and storing spatial information
and object information for the indoor according to a
recognition/reasoning level; b) analyzing an information request of the
service robots, transforming a format of the requested information to a
format analyzable by the service robot, and transmitting the transformed
information to the robot; c) receiving an information searching request
for searching a spatial information or an object information from the
robot; e) determining whether reasoning is required for searching
information or not, and searching and reasoning upper layer information
about the object or space using lower layer information obtained from
real environment or object, or searching and reasoning lower layer
information to be used for comprehension of the object or space from
upper layer information; f) searching requested object information or
requested spatial information; and g) transmitting searched spatial
information or searched object information to the requesting robot.

[0154]The spatial information or the object information includes: an
actual measurement information layer including actual measurement
information; a photometric information layer including photometric
features; a geometric information layer including information about
sub-parts obtained by dividing an object or a space by a geometric
structure; a structural information layer including information obtained
by dividing constituent elements of a space or an object and symbolizing
and layering information about the divided constituent elements; a
topological information layer including information for representing
locations of objects or obstacles in a space; a generic information layer
including information about generic models of a space, an object, or
constituent elements of the space or the object; a spatio-temporal
information layer including information about variation and relation of
objects or a space according to a time and a space; and a reasoning
information layer including reasoning information for reasoning about a
space, an object or states of the space or the object from object or
spatial information of lower information layers.

[0155]The actual measurement information layer for a space includes base
map information having geometric information of an indoor space. The
photometric information layer for a space includes a photometric feature
map of an indoor space. The geometric information layer for a space
includes geometric information of sub-parts obtained by dividing an
indoor space geometrically. The topological information layer for a space
includes a global coordinate or a pose of an object, or information about
an object recognized as an obstacle. The generic information layer for a
space includes semantic information for the space or constituent elements
of the space. The spatio-temporal information layer for a space includes
a brightness of light, a direction of lighting, a temperature, and a
humidity, which vary according to a temporal and spatial state of an
indoor.

[0156]The actual measurement information layer for an object includes
information of 2D/3D raw information that stores 2D or 3D representation
data obtained by actually measuring an object. The topological
information layer for an object includes information about accessible
directions represented by a plurality of 3D contact points and 3D
directional vectors. The spatio-temporal information layer for an object
includes information about an object-space temporal dependency, an object
presence and spatiotemporal dependency, an object-object spatiotemporal
dependency relation, an object-function spatiotemporal dependency, and an
object-physical feature spatiotemporal dependency. The reasoning
information layer for an object includes information about an evidence
structure formed as a graph representing relation between information of
lower information layers as a probability.

[0158]The obstacle information includes information represented as mesh or
cell.

[0159]The 2D or 3D representation data includes at least one of: a 2D raw
image calculated through at least two of camera angles; depth data
obtained from one of a laser scanner, a stereo camera, and a structured
light camera; and mesh data generated from the depth data.

[0160]In the step a), the spatial information or the object information is
composed and stored in ontology. In the step e), reasoning is performed
based on ontology.

[0161]In the step g), if requested information includes information about
a base map of the actual measurement information layer for a space and
object/obstacle location information of the topological information
layer, the interface generates a united map by combining the information
about the base map and the object/obstacle location information and
provides the united map to the robot.

[0162]The method further includes the steps of: a0) composing a
probability based behavior structure based on a given mission, which
decides unit behaviors to perform by a robot, and storing the composed
probability based behavior structure before the step a); and d) returning
the probability based behavior structure in response to a searching
request of the robot or extracting unit behaviors to perform and
necessary information to perform the unit behavior by analyzing the given
mission and returning the extracted unit behaviors and the extracted
necessary information after the step c).

[0163]In the step a0), the behavior structure is composed in a Bayesian
network having a probabilistic precedence relation of perception data, an
evidence structure and behaviors. In the step d), an optimal path is
decided based on a probability of the precedence relation and behaviors
on the selected path are extracted as unit behaviors to perform.

[0164]Also, the present invention relates to a computer readable recording
medium for storing a method for processing information for service robots
using a central information processing system communicating with at least
one of mobile service robots in an indoor.

[0165]Please, refer description of the central information processing
system according to the present invention to learn more about the central
information processing method for the service robot according to the
present invention.

[0166]It will be apparent to those skilled in the art that various
modifications and variations can be made to embodiments without departing
from the spirit or scope of the disclosed embodiments. Thus, it is
intended that the present invention covers modifications and variations
of this invention provided they come within the scope of the appended
claims and their equivalents.

[0167]The central information processing system and method according to
the present invention can be applied to a field for sharing and providing
necessary information to mobile service robots in an indoor space.
Particularly, the central information processing system and method
according to the present invention can be applied even though a plurality
of robots simultaneously operate in the same indoor space.

[0168]The central information processing system and method according to
the present invention integrally manage necessary information to enable
mobile service robots to share. Therefore, the central information
processing system and method according to the present invention improves
data management efficiency and reduces a spatial cost for storing
knowledge in a plurality of robots and a temporal cost for learning about
a space and objects.

[0169]The central information processing system and method according to
the present invention also provide information based on a
recognition/reasoning level of each mobile service robot. Therefore,
information can be integrally managed and robots can share information
although robots having different recognition/reasoning levels
simultaneously operate in the same indoor environment.

[0170]Furthermore, the central information processing system and method
according to the present invention provide information reasoned at high
level to service robots having a low recognition/reasoning level.
Therefore, a user may be able to receive a high level service
corresponding to a high cost mobile service robot using a low cost mobile
service robot.